Re: [PATCH 1/7] dt-bindings: media: i2c: Add DW9718S, DW9719 and DW9761 VCM

["André Apitzsch" <git@apitzsch.eu>]

Hi Daniel,

Am Mittwoch, dem 20.08.2025 um 16:56 -0500 schrieb Rob Herring:
> On Sun, Aug 17, 2025 at 07:09:20PM +0200, André Apitzsch wrote:
> > Document Dongwoon DW9718S, DW9719 and DW9761 VCM devicetree
> > bindings.
> > 
> > Signed-off-by: André Apitzsch <git@apitzsch.eu>
> > 
> > --
> > 
> > The possible values for sac-mode and vcm-prescale of DW9719 and
> > DW9761
> > are missing because there is no documentation available.
> > ---
> >  .../bindings/media/i2c/dongwoon,dw9719.yaml        | 115
> > +++++++++++++++++++++
> >  1 file changed, 115 insertions(+)
> > 
> > diff --git
> > a/Documentation/devicetree/bindings/media/i2c/dongwoon,dw9719.yaml
> > b/Documentation/devicetree/bindings/media/i2c/dongwoon,dw9719.yaml
> > new file mode 100644
> > index
> > 0000000000000000000000000000000000000000..80fd3fd42327fcafe3ff209d1
> > cd6bbe17b8a211b
> > --- /dev/null
> > +++
> > b/Documentation/devicetree/bindings/media/i2c/dongwoon,dw9719.yaml
> > @@ -0,0 +1,115 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/media/i2c/dongwoon,dw9719.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Dongwoon Anatech DW9719 Voice Coil Motor (VCM) Controller
> > +
> > +maintainers:
> > +  - devicetree@vger.kernel.org
> 
> No. Must be someone that has the h/w or cares about it. If there is
> no one, then we don't need the binding.

as you are listed as maintainer for DW9719 in MAINTAINERS, is it okay
if I add your name and e-mail here?

Best regards,
André

> 
> > +
> > +description:
> > +  The Dongwoon DW9718S/9719/9761 is a single 10-bit digital-to-
> > analog converter
> > +  with 100 mA output current sink capability, designed for linear
> > control of
> > +  voice coil motors (VCM) in camera lenses. This chip provides a
> > Smart Actuator
> > +  Control (SAC) mode intended for driving voice coil lenses in
> > camera modules.
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - dongwoon,dw9718s
> > +      - dongwoon,dw9719
> > +      - dongwoon,dw9761
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  vdd-supply:
> > +    description: VDD power supply
> > +
> > +  dongwoon,sac-mode:
> > +    description: |
> > +      Slew Rate Control mode to use: direct, LSC (Linear Slope
> > Control) or
> > +      SAC1-SAC6 (Smart Actuator Control).
> > +    $ref: /schemas/types.yaml#/definitions/uint32
> > +    enum:
> > +      - 0   # Direct mode
> > +      - 1   # LSC mode
> > +      - 2   # SAC1 mode (operation time# 0.32 x Tvib)
> > +      - 3   # SAC2 mode (operation time# 0.48 x Tvib)
> > +      - 4   # SAC3 mode (operation time# 0.72 x Tvib)
> > +      - 5   # SAC4 mode (operation time# 1.20 x Tvib)
> > +      - 6   # SAC5 mode (operation time# 1.64 x Tvib)
> > +      - 7   # SAC6 mode (operation time# 1.88 x Tvib)
> > +    default: 4
> > +
> > +  dongwoon,vcm-prescale:
> > +    description:
> > +      Indication of VCM switching frequency dividing rate select.
> > +    $ref: /schemas/types.yaml#/definitions/uint32
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - vdd-supply
> > +
> > +allOf:
> > +  - if:
> > +      properties:
> > +        compatible:
> > +          contains:
> > +            const: dongwoon,dw9718s
> > +    then:
> > +      properties:
> > +        dongwoon,sac-mode:
> > +          default: 4
> > +        dongwoon,vcm-prescale:
> > +          description:
> > +            The final frequency is 10 MHz divided by (value + 2).
> > +          minimum: 0
> 
> That's already the minimum being unsigned.
> 
> > +          maximum: 15
> > +          default: 0
> > +
> > +  - if:
> > +      properties:
> > +        compatible:
> > +          contains:
> > +            const: dongwoon,dw9719
> > +    then:
> > +      properties:
> > +        dongwoon,sac-mode:
> > +          default: 4
> > +        dongwoon,vcm-prescale:
> > +          default: 96
> > +
> > +  - if:
> > +      properties:
> > +        compatible:
> > +          contains:
> > +            const: dongwoon,dw9761
> > +    then:
> > +      properties:
> > +        dongwoon,sac-mode:
> > +          default: 6
> 
> At the top-level you already said the default is 4. The if/then is an
> AND operation. 'default' is just an annotation and has no effect on 
> validation. I would just drop it from the if/then altogether. It's
> not worth the complexity.
> 
> > +        dongwoon,vcm-prescale:
> > +          default: 62
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > +  - |
> > +    i2c {
> > +        #address-cells = <1>;
> > +        #size-cells = <0>;
> > +
> > +        actuator@c {
> > +            compatible = "dongwoon,dw9718s";
> > +            reg = <0x0c>;
> > +
> > +            vdd-supply = <&pm8937_l17>;
> > +
> > +            dongwoon,sac-mode = <4>;
> > +            dongwoon,vcm-prescale = <0>;
> > +        };
> > +    };
> > 
> > -- 
> > 2.50.1
> >